A liquid display device includes a plurality of sub-pixel units defined by a plurality of data lines intersecting with a plurality of gate lines. The plurality of sub-pixel units is in a matrix distribution, each sub-pixel unit includes a pixel electrode and a thin film transistor. A source electrode of the thin film transistor is connected with the data line, a drain electrode of the thin film transistor is connected with the pixel electrode, a gate electrode of the thin film transistor is connected with the gate line, and the gate line is connected with a gate drive circuit. The gate drive circuit controls turn-on and turn-off of the thin film transistor through the gate line. When the thin film transistor is turned on, the data line provides a data voltage to its corresponding pixel electrode through the thin film transistor, so as to charge the corresponding pixel electrode. During a display process, for each sub-pixel unit, the polarity of the data voltage corresponding to the Nth frame is opposite to the polarity of the data voltage corresponding to the (N+1)th frame. However, as the resolution increases, the turn-on time of the thin film transistor is shorter, which may cause the problem that voltage of the pixel electrode cannot reach a desired data voltage during the turn-on time of the thin film transistor, i.e., the problem of insufficient charge of the pixel electrode, thereby bringing adverse influence to the display effect.